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SQL SELECT speed int vs varchar
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Some rough benchmarks:
4 million records in Postgres 9.x
Table A = base table with some columns
Table B = Table A + extra column id of type bigint with random numbers
Table C = Table A + extra column id of type text with random 16-char ASCII strings
Results on 8GB RAM, i7, SSD laptop:
Siz...
What exactly is LLVM?
...el language can be represented in this LLVM IR format, then analysis tools based on this IR can be easily reused - that is the basic rationale.
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FormsAuthentication.SignOut() does not log the user out
...de caching in the Page_Load event of each page, or in the OnLoad() of your base page:
Response.Cache.SetCacheability(HttpCacheability.NoCache);
You might also like to call:
Response.Cache.SetNoStore();
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What is the maximum possible length of a .NET string?
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Based on my highly scientific and accurate experiment, it tops out on my machine well before 1,000,000,000 characters. (I'm still running the code below to get a better pinpoint).
UPDATE:
After a few hours, I've given up. Fi...
Modify Address Bar URL in AJAX App to Match Current State
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I ended up being a big fan of history.js to cover the bases for browser compatibility github.com/andreasbernhard/history.js
– jocull
Feb 11 '13 at 16:01
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When are you truly forced to use UUID as part of the design?
...dom - there are major components of the UUID that are time and/or location-based. So to have any real chance at a collision, the colliding UUIDs need tobe generated at the exact same time from different UUID generators. I'd say that while there is a reasonable chance that several UUID's might be ge...
What is the difference between indexOf() and search()?
...rals or string objects but not regular expressions. It also accepts a zero-based integer value to start its search from, e.g.:
"babyelephant".indexOf("e"); // gives you 4
"babyelephant".indexOf("e",5); // gives you 6 as the search
starts from 6th position or 5th index.
var m= /e/; "babyelephant"....
How do I determine the current operating system with Node.js
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On Mac the variable returns darwin. On Windows, it returns win32 (even on 64 bit).
Current possible values are:
aix
darwin
freebsd
linux
openbsd
sunos
win32
I just set this at the top of my jakeFile:
var isWin = process.platform === "win32";
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How to change the default charset of a MySQL table?
...t to apply this change for all tables that are not encoded in ut8 in a database, you can use this query and execute the resulted queries : SELECT concat('alter table ', table_name, ' CONVERT TO CHARACTER SET utf8 COLLATE utf8_general_ci;') FROM information_schema.tables WHERE table_schema='<yo...
使用虚拟现实和App Inventor进行实验 · App Inventor 2 中文网
...可以运行演示：根据演示设置，您会看到响应手机移动的图片或显示双眼图像的分屏。但您应该使用查看器以获得完整效果。如果您没有查看器，您可能首先想尝试没有查看器的演示，然后获取查看器进行更多探索。访问 Google ...